DNA汇集法高效筛查Vel阴性稀有血型的研究

Study on screening for Vel-rare blood type by DNA pooling

目的通过汇集标本的方法,建立高效筛查稀有血型的试验体系。方法根据Vel阴性(Vel-)稀有血型产生的分子机制,分别设计可特异扩增Vel血型基因SMIM1野生型序列和缺失突变序列的2组引物;合成Vel-对照质粒。将对照质粒与不同数量的随机标本进行汇集,根据扩增结果确定合适的汇集标本数;用缺失突变序列的特异性引物扩增汇集标本,如出现特异性目的条带,则用2组引物进行拆分检测参与汇集的标本,确认基因型。限制性片段长度多态性聚合酶链反应(PCR-RFLP)和DNA测序用于验证筛查结果。结果结合单个随机标本的浓度,最终确定4个血样汇集的筛查体系,可将试验所用时间及检测费用降低4倍。我们在9 122例标本中筛查到1例Vel血型基因SMIM1 c.64_80杂合缺失突变的个体。结论汇集方法的使用大大降低了筛查工作的时间和费用,可推广应用于具有类似分子机制的稀有血型的大规模筛查。

Objective To screen for rare blood type by the method of DNA pooling. Methods According to the genetic basis of Vel-rare blood type,primers specific for the SMIM1 c.64_80del allele and wide-type allele were designed. The control plasmid of Vel-was synthesized and functioned as a positive control. The control plasmid was mixed with a set number of random samples. Then,the PCR amplification result was detected by agarose gel electrophoresis to find an appropriate number of mixed random samples. Primers specific for the c.64_80del allele were used to amplify the mixed samples. Both primers specific for c.64_80del allele and wide-type allele were used to verify the genotype. PCR-RFLP and DNA sequencing were conducted to confirm the genotype. Results Taking into account the concentration of a single sample,four random samples were mixed as one template in a PCR-SSP reaction,which could reduce the time and financial cost of the screening system by four times. The screening of 9 122 blood donors revealed 1 individual who was heterozygous for the c.64_80del allele. Conclusion DNA pooling can greatly reduce the time and financial cost and can be widely used for screening rare blood type with similar genetic basis.